New pimarane diterpenoids with antibacterial activity from fungus Arthrinium sp. ZS03

A comprehensive chemical study of the endophytic fungus Arthrinium sp. ZS03, associated with Acorus tatarinowii Schott, yielded eleven pimarane diterpenoids (compounds 1-11), including seven novel compounds designated arthrinoids A-G (1-7). The determination of their structures and absolute configurations was achieved through extensive spectroscopic techniques, quantum chemical calculations of electronic circular dichroism (ECD), and single-crystal X-ray diffraction analysis. Furthermore, 7 demonstrated inhibitory activity against Klebsiella pneumoniae, comparable to the reference antibiotic amikacin, with a minimum inhibitory concentration (MIC) of 8 μg·mL-1.

Modified ent-Abietane Diterpenoids from the Leaves of Suregada zanzibariensis

The leaf extract of Suregada zanzibariensis gave two new modified ent-abietane diterpenoids, zanzibariolides A (1) and B (2), and two known triterpenoids, simiarenol (3) and β-amyrin (4). The structures of the isolated compounds were elucidated based on NMR and MS data analysis. Single-crystal X-ray diffraction was used to establish the absolute configurations of compounds 1 and 2. The crude leaf extract inhibited the infectivity of herpes simplex virus 2 (HSV-2, IC₅₀ 11.5 μg/mL) and showed toxicity on African green monkey kidney (GMK AH1) cells at CC₅₀ 52 μg/mL. The isolated compounds 1-3 showed no anti-HSV-2 activity and exhibited insignificant toxicity against GMK AH1 cells at ≥100 μM.

Wound healing properties of pharmaceutical gel containing isopimarane diterpene isolated from Kaempferia galanga L

ETHNOPHARMACOLOGICAL RELEVANCE

Kaempferia galanga L. rhizomes have been widely used in Thailand as medicine for treating inflammation and wound. A number of bioactive compounds have been isolated from the rhizomes of K. galanga and these compounds exhibited various pharmacological activities.

AIM OF THE STUDY

The objective of this study is to investigate the wound healing properties of gel containing 6β-acetoxysandaracopimaradiene-1α, 9α-diol (KG6), a compound from K. galanga.

MATERIALS AND METHODS

KG6 gel formulations were prepared using 1.0% carbopol 940 as gelling agent. Three KG6 gel formulations (0.10, 0.25, 0.50% w/w) were subjected to heating-cooling test to determine their physical, chemical and biological stabilities. The wound healing properties of KG6 gel formulations were performed using RAW264.7 cells for anti-inflammatory effect, while their impact on cell proliferation and migration, collagen content and H₂O₂-induced oxidative stress was examined using human dermal fibroblasts (HDF).

RESULTS

The pH, viscosity and general appearance after the heating-cooling test of the three prepared gels were stable in the acceptable range of gel formulation for skin. Gel containing 0.25% KG6 showed better chemical stability than other formulations. The 0.25% KG6 gel significantly increased cell viability (102.8%) and produced the highest HDF cell migration (91.9%) which was greater than that of Aloe vera gel (96.2, 78.4%, respectively). This gel exhibited anti-inflammatory activity via suppressing nitric oxide release and improved the viability of HDF cells against H₂O₂-induced oxidative stress. The 0.25% KG6 gels also increased collagen content in HDF cells.

CONCLUSION

The gel formulation consisting of 0.25% KG6 with 1.0% of carbopol 940 was found to be a promising pharmaceutical gel for wound treatments due to marked wound healing properties.

Pharmacokinetic characterization of carnosol from rosemary (Salvia Rosmarinus) in male C57BL/6 mice and inhibition profile in human cytochrome P450 enzymes

Rosemary (Salvia Rosmarinus) is a rich source of dietary diterpenes with carnosol as one of the major polyphenols used to standardize rosemary extracts approved as a food preservative, however, at present there is not any information on the murine pharmacokinetic profile of carnosol or its potential for drug interactions. The present study utilizes cell-free, cell-based, and animal-based experiments to define the pharmacokinetic profile of the food based phytochemical carnosol. Mice were administered carnosol (100 mg/kg body weight) by oral gavage and plasma levels were analyzed by LC-MS/MS to establish a detailed pharmacokinetic profile. The maximum plasma concentration exceeded 1 μM after a single administration. The results are significant as they offer insights on the potential for food-drug interactions between carnosol from rosemary and active pharmaceutical ingredients. Carnosol was observed to inhibit selected CYP450 enzymes and modulate metabolic enzymes and transporters in in vitro assays.

Taichunins E-T, Isopimarane Diterpenes and a 20-nor-Isopimarane, from Aspergillus taichungensis (IBT 19404): Structures and Inhibitory Effects on RANKL-Induced Formation of Multinuclear Osteoclasts

Fifteen new isopimarane-type diterpenes, taichunins E-S (1-15), and a new 20-nor-isopimarane, taichunin T (16), together with four known compounds were isolated from Aspergillus taichungensis (IBT 19404). The structures of these new compounds were determined by NMR and mass spectroscopy, and their absolute configurations were analyzed by NOESY and TDDFT calculations of ECD spectra. Taichunins G, K, and N (3, 7, and 10) completely inhibited the receptor activator of nuclear factor-κB ligand (RANKL)-induced formation of multinuclear osteoclasts in RAW264 cells at 5 μM, with 3 showing 92% inhibition at a concentration of 0.2 μM.

Bioassay-Guided Isolation of an Abetiane-Type Diterpenoid from Prunella vulgaris That Protects against Concanavalin A-Induced Autoimmune Hepatitis

Prunella vulgaris is a widely used edible Chinese medicinal plant. In the present study, two new abietane-type diterpenoids, abietoquinones A (1) and B (2), were isolated from this plant by an immunosuppressive bioassay-guided isolation procedure. Their structures were elucidated unambiguously by NMR spectroscopic analysis, single-crystal X-ray crystallography, and electronic circular dichroism calculations. Compounds 1 and 2 bear a cyclohex-2-ene-1,4-dione moiety, which is uncommon among abietane diterpenes. Also, abietoquinone A (1) suppressed murine splenocyte proliferation and decreased the production of proinflammatory cytokines induced by concanavalin A (Con A) in vitro. In Con A-challenged mice, preinjection with 1 significantly ameliorated liver injury. Additionally, abietoquinone A (1) exhibited inhibitory activities against the proliferation of murine splenocytes and human T cells induced by anti-CD3/anti-CD28 monoclonal antibodies (mAbs).

Diterpenoids with Aromatase Inhibitory Activity from the Rhizomes of Kaempferia elegans

Investigation of bioactive compounds from the rhizomes of Kaempferia elegans led to the isolation and characterization of ten new diterpenoids, namely, five 12,13-seco-diterpenoids named elegansins A-E (1-5) and five new abietanes, elegansols A-E (6-10), together with seven known diterpenoids (11-17). The structure elucidation of the new compounds was achieved by HRESIMS, NMR, and ECD spectroscopic analysis. Compounds (1-5) are the first examples of 12,13-seco-diterpenoid-type compounds representing a decalin fused dihydropyran skeleton. Plausible biosynthetic pathways for compounds 1-5 are proposed. Aromatase inhibitory activities of all compounds were evaluated, and abieta-8,11,13-trien-11-ol (16) was found to be the most potent aromatase inhibitor with an IC₅₀ value of 3.7 μM.

Rubesanolides F and G: Two Novel Lactone-Type Norditerpenoids from Isodon rubescens

A phytochemical investigation of the leaves of the medicinal plant Isodon rubescens led to the isolation of the two new degraded abietane lactone diterpenoids rubesanolides F (1) and G (2). Their structures were elucidated based on the analyses of the HRESIMS and 1D/2D NMR spectral data, and their absolute configurations were determined by ECD spectrum calculations and X-ray single crystal diffraction methods. Compounds 1 and 2, with a unique γ-lactone subgroup between C-8 and C-20, were found to form a carbonyl carbon at C-13 by removal of the isopropyl group in an abietane diterpene skeleton. Rubesanolide G (2) is a rare case of abietane that possesses a cis-fused configuration between rings B and C. The two isolates were evaluated for their biological activities against two cancer cell lines (A549 and HL60), three fungal strains (Candida alba, Aspergillus niger and Rhizopus nigricans) and three bacterial strains (Escherichia coli, Staphylococcus aureus and Bacillus subtilis).

Nor-abietane Diterpenoids from Perovskia abrotanoides Roots with Anti-inflammatory Potential

Fractionation of an EtOAc extract of the roots of Perovskia abrotanoides yielded 28 diterpenoids, including 12 new analogues, 1-12. The structures of these diterpenoids were established using comprehensive spectroscopic data analysis, including 1D and 2D NMR, high-resolution electrospray ionization mass spectrometry, electronic circular dichroism spectroscopy, and comparison with literature data. The extract and some of the tested compounds showed significant anti-inflammatory activity on J774A.1 macrophage cells stimulated with E. coli lipopolysaccharide. In particular, the tested compounds significantly inhibited the release of nitric oxide and the expression of related proinflammatory enzymes, such as inducible nitric oxide synthase.

(9βH)- and 17-Nor-Pimaranes from Icacina oliviformis

Eleven pimarane-type diterpenoids were isolated from the tubers of Icacina oliviformis, including three new compounds, icacinlactone M (9), icacinlactone H 2-O-β-d-glucopyranoside (10), and icacinlactone N 3-O-β-d-glucopyranoside (11), together with an artifact of acrenol (8). Among the known structures, icacinlactone A (2), icacinlactone B (3), icacinlactone H (4), 12-hydroxyicacinlactone A (5), 14α-methoxyhumirianthol (6), and annonalide (7) are reported from I. oliviformis for the first time, whereas icacinol (1) has previously been found in this plant. Icacinol, 14α-methoxyhumirianthol, and annonalide displayed moderate cytotoxic activity in a panel of human cancer cell lines.

Sequential extraction of carnosic acid, rosmarinic acid and pigments (carotenoids and chlorophylls) from Rosemary by online supercritical fluid extraction-supercritical fluid chromatography

A high degree of selectivity is required during the plant extraction process in order to obtain extracts enriched in specific compounds or to avoid the extraction of unwanted ones. Rosemary is well known for its antioxidant compounds (carnosic acid, carnosol and rosmarinic acid). The plant also contains pigments (i.e. carotenoids, chlorophylls) which may cause a colour problem during the use of the extract in cosmetic formulations, for example. Supercritical fluid extraction is considered as a selective technique for plant extraction. Due to the physico-chemical properties of supercritical fluids, related to pressure, temperature and modifier addition, it is possible to carry out sequential extraction with successive conditions to collect different fractions that are rich either in pigments or in bioactive compounds. The aim of this study was to selectively extract bioactive compounds (i.e. carnosic acid and rosmarinic acid) and pigments (carotenoids and chlorophylls) from rosemary using supercritical fluid extraction. The optimisation of the extraction method was carried out using supercritical fluid extraction online coupled with a supercritical fluid chromatography (SFE-SFC) system. Two columns of different polarities were coupled to achieve the separation of the targeted compounds every five minutes during the extraction. Four fractions were obtained: a first one rich in carotenoids obtained with pure CO2 (25°C and 20 MPa), a second rich in carnosic acid obtained with 3% polar modifier (EtOH:water 50/50 v/v), a third fraction rich in rosmarinic acid using 10% of the same modifier and a fourth fraction rich in chlorophylls with 30% of ethanol as modifier. These four samples were then analysed by UHPLC-DAD-ESI-QTOF-HRMS in order to identify other extracted compounds and to study how the selected conditions impacted their extraction.

Inhibition of tanshinone IIA on renin activity protected against osteoporosis in diabetic mice

Context: Salvia miltiorrhiza Bge. (Labiatae) (SMB) is applied clinically for management of diabetic osteoporosis in China, and research results has suggested its potential action on renin-angiotensin system (RAS).Objective: This study screens and explores naturally occurring bioactive constituents from the root of SMB acting on renin activity and evaluates its osteoprotective efficacy in diabetic mice.Materials and methods: Human embryonic kidney (HEK) 293 cells, engineered to express human renin, were used as an in vitro model to identify bioactive compound, tanshinone IIA, inhibiting renin activity. The C57BL/6 mice (n = 10 in each group) with diabetes induced by streptozotocin (STZ) were intraperitoneally injected with tanshinone IIA (10 and 30 mg/kg). The mice without STZ treatment and the diabetic mice treated with aliskiren were used as non-diabetic control and positive control, respectively.Results: Tanshinone IIA was found to display inhibitory effects on renin activity of HEK-293 cells; moreover, it down-regulated protein expression of ANG II in human renin-expressed HEK-293 cells. Treatment of diabetic mice with tanshinone IIA with both doses could significantly decrease ANG II level in serum (from 16.56 ± 1.70 to 10.86 ± 0.68 and 9.14 ± 1.31 pg/mL) and reduce ANG II expression in bone, consequently improving trabecular bone mineral density and micro-structure of proximal tibial end and increasing trabecular bone area of distal femoral end in diabetic mice.Conclusions: This study revealed beneficial effects of tanshinone IIA on bone of diabetic mice, and potentially suggested the application of Salvia miltiorrhiza in the treatment of osteoporosis and drug development of tanshinone IIA as a renin inhibitor.

Anti-Obesity Effects of Tanshinone I from Salvia miltiorrhiza Bunge in Mice Fed a High-Fat Diet through Inhibition of Early Adipogenesis

Tanshinone I (Tan I) is a diterpenoid isolated from Salvia miltiorrhiza Bunge and exhibits antitumor effects in several cancers. However, the anti-obesity properties of Tan I remain unexplored. Here, we evaluated the anti-obesity effects of Tan I in high-fat-diet (HFD)-induced obese mice and investigated the underlying molecular mechanisms in 3T3-L1 cells. HFD-induced obese mice were orally administrated Tan I for eight weeks, and body weight, weight gain, hematoxylin and eosin staining and serum biological parameters were examined. The adipogenesis of 3T3-L1 preadipocytes was assessed using Oil Red O staining and measurement of intracellular triglyceride (TG) levels, and mitotic clonal expansion (MCE) and its related signal molecules were analyzed during early adipogenesis of 3T3-L1 cells. The administration of Tan I significantly reduced body weight, weight gain, and white adipocyte size, and improved obesity-induced serum levels of glucose, free fatty acid, total TG, and total cholesterol in vivo in HFD-induced obese mice. Furthermore, Tan I-administered mice demonstrated improvement of glucose metabolism and insulin sensitivity. Treatment with Tan I inhibited the adipogenesis of 3T3-L1 preadipocytes in vitro, with this inhibition mainly occurring at an early phase of adipogenesis through the attenuation of MCE via cell cycle arrest at the G1/S phase transition. Tan I inhibited the phosphorylation of p38, extracellular signal-regulated kinase (ERK), and Akt during the process of MCE, while it stimulated the phosphorylation of AMP-activated protein kinase. Furthermore, Tan I repressed the expression of CCAAT-enhancer-binding protein β (C/EBPβ), histone H3K9 demethylase JMJD2B, and subsequently cell cycle genes. Moreover, Tan I regulated the expression of early adipogenic transcription factors including GATAs and Kruppel-like factor family factors. These results indicate that Tan I prevents HFD-induced obesity via the inhibition of early adipogenesis, and thus improves glucose metabolism and insulin sensitivity. This suggests that Tan I possesses therapeutic potential for the treatment of obesity and obesity-related diseases.

Antibacterial and ATP Synthesis Modulating Compounds from Salvia tingitana

A surface extract of the aerial parts of Salvia tingitana afforded a nor-sesterterpenoid (1) and eight new sesterterpenoids (2-̵9), along with five known sesterterpenoids, five labdane and one abietane diterpenoid, one sesquiterpenoid, and four flavonoids. The structures of the new compounds were established by 1D and 2D NMR spectroscopy, HRESIMS, and VCD data and Mosher's esters analysis. The antimicrobial activity of compounds was evaluated against 30 human pathogens including 27 clinical strains and three isolates of marine origin for their possible implications on human health. The methyl ester of salvileucolide (10), salvileucolide-6,23-lactone (11), sclareol (15), and manool (17) were the most active against Gram-positive bacteria. The compounds were also tested for the inhibition of ATP production in purified mammalian rod outer segments. Terpenoids 10, 11, 15, and 17 inhibited ATP production, while only 17 inhibited also ATP hydrolysis. Molecular modeling studies confirmed the capacity of 17 to interact with mammalian ATP synthase. A significant reduction of ATP production in the presence of 17 was observed in Enterococcus faecalis and E. faecium isolates.

Anti-Migratory and Pro-Apoptotic Properties of Parvifloron D on Triple-Negative Breast Cancer Cells

Medicinal plants are important sources of new bioactive compounds with potential anticancer activity. Parvifloron D (ParvD) is an abietane diterpenoid, isolated in high amounts from Plectranthus ecklonii Benth. Previous reports have suggested potential therapeutic properties for ParvD. ParvD has shown pro-apoptotic and cytotoxic effects in leukemia and melanoma cell lines. However, to the best of our knowledge, there are no studies in triple-negative breast cancer (TNBC) models. TNBC is a breast cancer subtype characterized by an aggressive behavior with poor clinical outcomes and weak overall therapeutic responses to the current treatment options. This work aimed at evaluating the anticancer effect of ParvD in MDA-MB-231 cells, a model of human TNBC. To obtain sufficient amounts of purified ParvD the efficiency of several extraction methods was compared. ParvD (0.1–10 µM) decreased cell viability in a concentration-dependent manner. Treatment with ParvD (5 µM) significantly increased the percentage of apoptotic nuclei and exposure to 3 µM ParvD increased the sub-G1 population. Since altered cell adherence, migration, and invasion are determinant processes for the formation of metastases, the effect of ParvD on these cellular processes was tested. Although treatment with ParvD (1 µM) had no effect on cell-substrate attachment, ParvD (1 µM) significantly reduced cell chemotaxis and invasion. This is the first report describing the proapoptotic effect of ParvD in TNBC cells. Moreover, for the first time we have shown that ParvD reduces cell motility, unraveling potential anti-metastatic properties.

Antidiabetic Effects and Mechanisms of Rosemary (Rosmarinus officinalis L.) and its Phenolic Components

Diabetes mellitus is a chronic endocrine disease result from absolute or relative insulin secretion deficiency, insulin resistance, or both, and has become a major and growing public healthy menace worldwide. Currently, clinical antidiabetic drugs still have some limitations in efficacy and safety such as gastrointestinal side effects, hypoglycemia, or weight gain. Rosmarinus officinalis is an aromatic evergreen shrub used as a food additive and medicine, which has been extensively used to treat hyperglycemia, atherosclerosis, hypertension, and diabetic wounds. A great deal of pharmacological research showed that rosemary extract and its phenolic constituents, especially carnosic acid, rosmarinic acid, and carnosol, could significantly improve diabetes mellitus by regulating glucose metabolism, lipid metabolism, anti-inflammation, and anti-oxidation, exhibiting extremely high research value. Therefore, this review summarizes the pharmacological effects and underlying mechanisms of rosemary extract and its primary phenolic constituents on diabetes and relative complications both in vitro and in vivo studies from 2000 to 2020, to provide some scientific evidence and research ideas for its clinical application.

Glucose Uptake Stimulatory and PTP1B Inhibitory Activities of Pimarane Diterpenes from Orthosiphon stamineus Benth

Seven pimarane diterpenes (1–7) were isolated from Orthosiphon stamineus Benth. by assay-guided isolation. All of the isolates possessed a 2-deoxy-2-((7-nitro-2,1,3-benzoxadiazol-4-yl)amino)-d-glucose uptake effect in 3T3-L1 adipocytes at concentrations of 5 and 10 μM. Most of them showed potent inhibition against protein tyrosine phosphatase 1B with IC₅₀ values ranging from 0.33 to 9.84 μM. In the kinetic study, all inhibition types were exposed for the examined potencies, including mixed-competitive (1), non-competitives (3 and 5), competitive (6), and uncompetitive (7). The results suggested that O. stamineus and its pimarane diterpenes might exert the hypoglycemic effect via the insulin signaling pathway targeting inhibition of protein tyrosine phosphatase 1B (PTP1B) activity.

Basimarols A, B, and C, Highly Oxygenated Pimarane Diterpenoids from Basilicum polystachyon

The highly oxygenated pimarane diterpenoids basimarols A, B, and C (3-5) were isolated from the plant species Basilicum polystachyon, which was collected within the Australian arid zone. Structure elucidation was performed using a suite of spectroscopic techniques, including X-ray crystallography. Anticancer and anti-DENV activity of 3-5 was explored, but only limited activity was observed. More extensive antiviral evaluation of stachyonic acid A (1), which was also isolated from B. polystachyon, revealed broad spectrum antiviral activity against West Nile virus (Kunjin strain, WNV_Kun) and human influenza viruses H1N1 and H3N2.

Parvifloron D from Plectranthus strigosus: Cytotoxicity Screening of Plectranthus spp. Extracts

The Plectranthus genus is commonly used in traditional medicine due to its potential to treat several illnesses, including bacterial infections and cancer. As such, aiming to screen the antibacterial and cytotoxic activities of extracts, sixteen selected Plectranthus species with medicinal potential were studied. In total, 31 extracts obtained from 16 Plectranthus spp. were tested for their antibacterial and anticancer properties. Well diffusion method was used for preliminary antibacterial screening. The minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values of the five most active acetonic extracts (P. aliciae, P. japonicus, P. madagascariensis var. “Lynne”, P. stylesii, and P. strigosus) were determined. After preliminary toxicity evaluation on Artemia salina L., their cytotoxic properties were assessed on three human cancer cell lines (HCT116, MCF-7, and H460). These were also selected for mechanism of resistance studies (on NCI-H460/R and DLD1-TxR cells). An identified compound—parvifloron D—was tested in a pair of sensitive and MDR-Multidrug resistance cancer cells (NCI-H460 and NCI-H460/R) and in normal bronchial fibroblasts MRC-5. The chemical composition of the most active extract was studied through high performance liquid chromatography with a diode array detector (HPLC-DAD/UV) and liquid chromatography–mass spectrometry (LC–MS). Overall, P. strigosus acetonic extract showed the strongest antimicrobial and cytotoxic potential that could be explained by the presence of parvifloron D, a highly cytotoxic diterpene. This study provides valuable information on the use of the Plectranthus genus as a source of bioactive compounds, namely P. strigosus with the potential active ingredient the parvifloron D.

Anti-cholinesterase activities of constituents isolated from Lycopodiastrum casuarinoides

Phytochemical investigation of the ethyl acetate extract of Lycopodiastrum casuarinoides (Spring) Holub (Lycopodiaceae) led to the isolation of nine compounds, including two new serratene triterpenoids, serrat-14-en-3α,21α-diol (1), 26-nor-8-oxo-21-one-α-onocerin (6), one new abietane diterpenoid, lycocasuarinone A (7), one new sesquiterpene acid, 7, 9-diene-1,4-epoxy-2-hydroxy-10-carboxylic acid (8) and one new chromone derivative, 5,7-dihydroxy-2-methyl esterchromone (9), together with four known serratene triterpenoids (2-5). Abietane diterpenoid (7) and sesquiterpene acid (8) from Lycopodiastrum casuarinoides are reported for the first time. Their structures and stereochemistry were unambiguously elucidated by spectroscopic analysis and comparison with known ones. All the compounds were tested for acetylcholinesterase (AChE) and butyrocholinesterase (BuChE) inhibitory activities. Bioactivity assays revealed that compound 6 exhibited the most potent AChE inhibitory effect.

Characterization of Phenolic Compounds and Antiproliferative Effects of Salvia pomifera and Salvia fruticosa Extracts

The phenolic compounds of methanolic extracts of Salvia pomifera and Salvia fruticosa were identified by liquid chromatography tandem mass spectrometry. Carnosic acid and its metabolite carnosol were the most abundant terpene phenolic compounds of S. fruticosa, while they were completely absent in S. pomifera. The main terpene phenolic constituent of S. pomifera was 12-O-methylcarnosic acid and its mass/mass fragmentation pathway was explained. The detailed mechanism of carnosic acid oxidation to carnosol was suggested. The effects of Salvia extracts and/or carnosic acid, the main diterpene phenolic component of S. fruticosa, on the proliferation and cell cycle of two melanoma cell lines (A375, Mel JuSo) and human fibroblast cell line (HFF) were investigated by MTT assay, PI-exclusion assay and flow cytometry cell cycle analysis. Extract of S. fruticosa more efficiently than S. pomifera extract reduced the proliferation of the human melanoma cells. Carnosic acid showed the most significant effect. The first evidence that carnosic acid affects microtubule dynamics and arrests the cell cycle in the G2/M phase was provided. Collectively, our results demonstrate that these two Salvia species are plants of medicinal interest with perspective for further investigation. Carnosic acid could be the compound responsible for the biological activities of S. fruticosa extracts.

Bioactive Dimeric Abietanoid Peroxides from the Bark of Cryptomeria japonica

Three new dimeric abietane-type diterpenoids, abieta-6,8,11,13-tetraen-12-yl 12-hydroxyabieta-8,11,13-trien-7α-yl peroxide (1), abieta-6,8,11,13-tetraen-12-yl 12-hydroxyabieta-8,11,13-trien-7β-yl peroxide (2), and 12-hydroxyabieta-8,11,13-trien-7β-yl 7-oxoabieta-5,8,11,13-tetraen-12-yl peroxide (3), together with four known abietane-type diterpenoids (4–7) were isolated from the methanol extract of the bark of Cryptomeria japonica. Their structures were elucidated on the basis of spectroscopic analysis and comparison of NMR data with those of known analogues. At a concentration of 50 μM, compounds 1, 2, and 3 showed 26.2%, 23.6%, and 35.7% inhibition towards xanthine oxidase enzyme, respectively. In addition, compound 3 also showed 24.9% inhibition toward angiotensin-converting enzyme (ACE).

A Pair of Enantiomeric Bis- seco-abietane Diterpenoids from Cryptomeria fortunei

(±)-Cryptomeriolide, a pair of racemic bis- seco-abietane diterpenoids, were isolated from the bark of Cryptomeria fortunei. The separation of enantiomers was achieved by using chiral stationary phase HPLC. Their structures including the absolute configuration and conformations in solution and solid state were determined by extensive analysis of spectroscopic data, single-crystal X-ray diffraction, and comparison of calculated and experimental electronic circular dichroism data. A bioinspired one-pot enantiomeric synthesis of 1a and 1b was accomplished via a readily made intermediate orthoquinone from sugiol. All compounds including the synthetic intermediates were assayed for their cytotoxic activities on human cancer cell lines HL-60, A549, and SGC7901.

Enhanced production of tanshinone IIA in endophytic fungi Emericella foeniculicola by genome shuffling

CONTEXT

Tanshinone IIA, commercially produced from Salvia miltiorrhiza Bunge (C.Y.Wu) (Labiatae), has various biological benefits. Currently, this compound is mainly extracted from plants. However, because of the long growth cycle and the unstable quality of plants, the market demands can barely be satisfied.

OBJECTIVE

The genomic shuffling technology is applied to screen the high-yield tanshinone IIA strain, which could be used to replace the plant S. miltiorrhiza for the production of tanshinone IIA. The change in the production of tanshinone IIA is clarified by comparing it with the original strain.

MATERIALS AND METHODS

Tanshinone IIA was extracted from Strains cells, which was prepared through 0.5 mL protoplast samples by using hypertonic solution I from two different strains. Then, it was analyzed by high-performance liquid chromatography at 30 °C and UV 270 nm. Total DNA from the strains was extracted for RAPD amplification and electrophoresis to isolate the product.

RESULTS

In this study, a high-yield tanshinone IIA strain F-3.4 was screened and the yield of tanshinone IIA was increased by 387.56 ± 0.02 mg/g, 11.07 times higher than that of the original strain TR21.

DISCUSSION

This study shows that the genetic basis of high-yield strains is achieved through genome shuffling, which proves that genome shuffling can shorten the breeding cycle and improve the mutagenesis efficiency in obtaining the strains with good traits and it is a useful method for the molecular breeding of industrial strains.

Potent, Irreversible Inhibition of Human Carboxylesterases by Tanshinone Anhydrides Isolated from Salvia miltiorrhiza ("Danshen")

The roots of Salvia miltiorrhiza ("Danshen") have been used in Chinese herbal medicine for centuries for a host of different conditions. While the exact nature of the active components of this material are unknown, large amounts of tanshinones are present in extracts derived from these samples. Recently, the tanshinones have been demonstrated to be potent human carboxylesterase (CE) inhibitors, with the ability to modulate the biological activity of esterified drugs. During the course of these studies, we also identified more active, irreversible inhibitors of these enzymes. We have purified, identified, and synthesized these molecules and confirmed them to be the anhydride derivatives of the tanshinones. These compounds are exceptionally potent inhibitors ( K_i < 1 nM) and can inactivate human CEs both in vitro and in cell culture systems and can modulate the metabolism of the esterified drug oseltamivir. Therefore, the coadministration of Danshen extracts with drugs that contain the ester chemotype should be minimized since, not only is transient inhibition of CEs observed with the tanshinones, but also prolonged irreversible inhibition arises via interaction with the anhydrides.

Phytotoxic ent-Isopimarane-Type Diterpenoids from Euphorbia hylonoma

Thirteen new ent-isopimarane-type diterpenoids, 1-10 and 14-16, and seven known diterpenoids, 11-13 and 17-20, were isolated from the roots of Euphorbia hylonoma. Among these compounds, four pairs of C-12 epimers (1 vs 2, 4 vs 5, 12 vs 13, and 14 vs 15) were identified. The structures of the new diterpenoids were elucidated using spectroscopic data analyses, electronic circular dichroism, and single-crystal X-ray diffraction data. The phytotoxic effects of compounds 1-20 on the growth of the roots and shoots of Poa annua and Festuca arundinacea seedlings were evaluated. Among the tested diterpenoids, 18 was the most active for inhibiting the growth of P. annua seedlings, and this compound was as active as glyphosate.

Anti-inflammatory and antiproliferative diterpenoids from Plectranthus scutellarioides

Chemical investigation of the dichloromethane extract of the aerial parts of Plectranthus scutellarioides led to the isolation and characterization of 10 diterpenoids with an abietane skeleton and one cembrane-type diterpenoid. Among them, six have not yet been described in the literature. Their structures were established by 1D and 2D NMR, UV and IR spectroscopy, and HRESIMS. The relative configuration was determined by Gauge-Independent Atomic Orbital NMR chemical shift calculations supported by the advanced statistical method DP4 plus and further confirmed by electronic circular dichroism. The isolated constituents were evaluated for their in vitro NF-κB inhibitory activity, as well as for their cytotoxic effects in human multiple myeloma cancer stem cells and RPMI 8226 tumor cell line. Coleon O, coleon G, lanugone K and 6-acetylfredericone B showed the highest inhibitory effect against NF-κB, displaying IC₅₀ of 11.2, 11.0, 4.5 and 9.7 μM, respectively. Coleon O exhibited also a significant activity towards human multiple myeloma cancer stem cells and RPMI 8226 cells with IC₅₀ of 9.2 and 8.4 μM, respectively.

First Evidence of Dehydroabietic Acid Production by a Marine Phototrophic Gammaproteobacterium, the Purple Sulfur Bacterium Allochromatium vinosum MT86

The production of secondary metabolites by a new isolate of the purple sulfur bacterium Allochromatium vinosum, which had shown antibiotic activities during a preliminary study, revealed the production of several metabolites. Growth conditions suitable for the production of one of the compounds shown in the metabolite profile were established and compound 1 was purified. The molecular formula of compound 1 (C₂₀H₂₈O₂) was determined by high resolution mass spectra, and its chemical structure by means of spectroscopic methods. The evaluation of these data revealed that the structure of the compound was identical to dehydroabietic acid, a compound known to be characteristically produced by conifer trees, but so far not known from bacteria, except cyanobacteria. The purified substance showed weak antibiotic activities against Bacillus subtilis and Staphylococcus lentus with IC₅₀ values of 70.5 µM (±2.9) and 57.0 µM (±3.3), respectively.

Libertellenones O-S and Eutypellenones A and B, Pimarane Diterpene Derivatives from the Arctic Fungus Eutypella sp. D-1

Seven new pimarane-type diterpene derivatives, libertellenones O-S (1-5) and eutypellenones A and B (6 and 7), together with two known compounds (8 and 9), were isolated from the culture of Eutypella sp. D-1 obtained from high-latitude soil of the Arctic. Their structures were elucidated from spectroscopic data, as well as experimental and calculated electronic circular dichroism (ECD) analysis. Structurally, compounds 1-5 possess a cyclopropyl-fused pimarane diterpene moiety, whereas compounds 6 and 7 share an unusual cyclobutyl-fused pimarane diterpene skeleton. Compounds 1-9 exhibited cytotoxicities against HeLa, MCF-7, HCT-116, PANC-1, and SW1990 cells, with IC₅₀ values in the range of 0.3 to 29.4 μM. Compounds 6 and 7 could dose-dependently inhibit the activity of NF-κB and exhibited significantly inhibitory effects on nitric oxide production induced by lipopolysaccharide.

Abietane Diterpenoids from the Roots of Clerodendrum trichotomum and Their Nitric Oxide Inhibitory Activities

Twelve new abietane diterpenoids (1-12) and 31 known analogues (13-43) were isolated from a medicinal Chinese herb, Clerodendrum trichotomum Thunberg. The absolute configurations of 1-3 were established on the basis of ECD and X-ray crystallography data, whereas that of 4 was elucidated by comparison of experimental and calculated ECD data. Eight diterpenoids, 15,16-dehydroteuvincenone G (1), trichotomin A (4), 2α-hydrocaryopincaolide F (7), villosin C (20), 15-dehydro-17-hydroxycyrtophyllone A (22), demethylcryptojaponol (38), 6β-hydroxydemethylcryptojaponol (39), and trichotomone (43), exerted inhibitory effects against NO production with IC₅₀ values of 5.6-16.1 μM. The structure-activity relationships of the isolated diterpenoids are also estimated.

Simultaneous purification of dihydrotanshinone, tanshinone I, cryptotanshinone, and tanshinone IIA from Salvia miltiorrhiza and their anti-inflammatory activities investigation

Dihydrotanshinone, tanshinone I, cryptotanshinone, and tanshinone IIA are major lipid-soluble constituents isolated from Salvia miltiorrhiza Bunge (Danshen). In the present study, a systematic method was developed to simultaneously isolate and purify those compounds using macroporous adsorption resins and semi-preparative HPLC with a dynamic axial compress (DAC) system. The Danshen extract (95% alcohol) was divided into three fractions using different concentrations of alcohol (0%, 45%, and 90%) on D101 column. The content of total tanshinones of 90% alcohol eluent (TTS) was over 97%. Furthermore, the anti-inflammatory effects of those samples were investigated on LPS-stimulated RAW264.7 cells and three animal models. The results showed that the anti-inflammatory effect of TTS in vitro was superior to the one of any other sample including 0% and 45% eluent, and total tanshinones capsules. In addition, TTS exhibited a stronger anti-inflammatory effect than that of dihydrotanshinone, tanshinone IIA, cryptotanshinone, and tanshinone I, respectively. For animal models, TTS could significantly suppress xylene-induced ear oedema and rescue LPS-induced septic death and acute kidney injury in mice. In summary, the separation process developed in the study was high-efficiency, economic, and low-contamination, which was fit to industrial producing. TTS is a potential agent for the treatment of inflammatory diseases.

Isolation, Characterization, and Structure-Activity Relationship Analysis of Abietane Diterpenoids from Callicarpa bodinieri as Spleen Tyrosine Kinase Inhibitors

Species belonging to the genus Callicarpa are used traditionally in Chinese medicine for the treatment of inflammation, rheumatism, and pain. Investigation of the leaves and twigs of Callicarpa bodinieri resulted in the isolation of nine new abietane diterpenoids, bodinieric acids A-I (1-9), along with six known compounds (10-15). The structures of 1-9 were elucidated on the basis of the interpretation of their HRESIMS and NMR data and by ECD calculations. To explore the potential therapeutic target of this plant for immune-mediated disease, the inhibitory activities of the isolates obtained were determined against 13 kinase enzymes. Eight compounds exhibited moderate inhibitory effects on spleen tyrosine kinase (SYK), and the IC₅₀ values of compounds 2 and 6 were 7.2 and 10.7 μM, respectively. In addition, a preliminary structure-activity relationship of this scaffold was analyzed with both molecular docking and a 3D-QSAR pharmacophore model.

Anti-neuroinflammatory diterpenoids from the endangered conifer Podocarpus imbricatus

Ten diterpenoids including three new abietanes (1-3) were isolated from the twigs and needles of Podocarpus imbricatus, an endangered conifer growing in a Cantonese garden. The new structures were established by means of spectroscopic methods. Among the isolates, 3β-hydroxy-abieta-8,11,13-trien-7-one (5), decandrin G (6), and 7,15-pimaradien-18-oic acid (8) showed significant anti-neuroinflammatory activities by inhibiting the overproduction of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated murine BV-2 microglial cells, with IC₅₀ values of 3.7, 11.1, and 4.5 μM, respectively.

Three New Abietane-Type Diterpenoids from Plectranthus africanus and Their Antibacterial Activities

Three new abietane-type diterpenoids, plectranthroyleanones A - C (1:  - 3: ), together with five known compounds (4:  - 8: ) were isolated from the methanol extract of the whole plant of Plectranthus africanus using column chromatography techniques. The structures of the new compounds were elucidated using a combination of 1D and 2D NMR and HRESIMS analyses. Compound 1: exhibited weak activities with minimal inhibitory concentration values of 75 µg/mL against gram-positive bacteria, Bacillus subtilis and Staphylococcus aureus, and 150 µg/mL against two gram-negative bacteria, Pseudomonas aeruginosa and Klebsiella pneumoniae, respectively, while 2: and 3: had moderate antibacterial activity against K. pneumoniae with a minimal inhibitory concentration value of 37.5 µg/mL.

Hypersensitivity of BRCA2 deficient cells to rosemary extract explained by weak PARP inhibitory activity

Rosemary extract is used in food additives and traditional medicine and has been observed to contain anti-tumor activity. In this study, rosemary extract is hypothesized to induce synthetic lethality in BRCA2 deficient cells by PARP inhibition. Chinese hamster lung V79 cells and its mutant cell lines, V-C8 (BRCA2 deficient) and V-C8 with BRCA2 gene correction were used. Rosemary extract and its major constituent chemicals were tested for their cytotoxicity by colony formation assay in cells of different BRCA2 status. The latter chemicals were tested for inhibitory effect of poly (ADP-ribose) polymerase (PARP) activity in vitro and in vivo. Rosemary has shown selective cytotoxicity against V-C8 cells (IC50 17 µg/ml) compared to V79 cells (IC50 26 µg/ml). Among tested chemicals, gallic acid and carnosic acid showed selective cytotoxicity to V-C8 cells along with PARP inhibitory effects. Carnosol showed comparative PARP inhibitory effects at 100 µM compared to carnosic acid and gallic acid, but the selective cytotoxicity was not observed. In conclusion, we predict that within rosemary extract two specific constituent components; gallic acid and carnosic acid were the cause for the synthetic lethality.

Antifatigue properties of tanshinone IIA in mice subjected to the forced swimming test

CONTEXT

Tanshinone IIA (Tan IIA) is a constituent of Danshen Salvia miltiorrhiza Bunge (Lamiaceae); however, its antifatigue activity remains unclear.

OBJECTIVE

To study the antifatigue properties of Tan IIA and its underlying mechanisms.

MATERIALS AND METHODS

In program I, three mouse groups were separately subjected to three gavages with 0, 1 and 6 mg/kg Tan IIA and forced swimming test (FST) weekly for 8 weeks; in program II, one gavage with 0, 2 and 10 mg/kg Tan IIA was administered plus FST weekly for 4 weeks. Serum glucose, lactate, superoxide dismutase (SOD), malondialdehyde (MDA) and blood urea nitrogen (BUN) were determined after final FST.

RESULTS

Tan IIA significantly prolonged swimming durations in program I but not in program II. Swimming times were 3208 ± 1054 and 2443 ± 1054 s for the 1 and 6 mg/kg treatments and 856 ± 292 s for the vehicle control. The two doses significantly reduced serum glucose levels (40.3 ± 8.5 and 60.0 1 ± 11.8 mg/kg) and lactate levels (61.3 ± 27.5 and 68.8 ± 8.5 mg/kg) in treated mice compared with those in control mice (137.5 ± 38.6 mg/kg and 122.7 ± 18.2 mg/kg, respectively). However, no significant differences were observed regarding SOD, MDA or BUN levels.

DISCUSSION AND CONCLUSIONS

Tan IIA has antifatigue activity and is associated with reductions in serum glucose and lactate levels. Further studies should assess muscle hypertrophy and efficient aerobic glycolysis caused by Tan IIA. Tan IIA has potential as a pharmacological agent for fatigue resistance.

Roscotanes and roscoranes: Oxygenated abietane and pimarane diterpenoids from Kaempferia roscoeana

Eight previously undescribed ditepenoids, including four oxygenated abietanes (roscotanes A-D) and four oxygenated pimaranes (roscoranes A-D), along with twelve known diterpenoids were isolated from the whole plants of Kaempferia roscoeana. Their structures were elucidated by extensive spectroscopic analysis, and the structure of roscotane A was further confirmed by single crystal X-ray diffraction analysis. Most isolated compounds were evaluated for their antimicrobial and antimalarial activities.

Phytochemical and biological evaluation of Salvia apiana

Salvia apiana (white sage, Lamiaceae family) plant is native to southern California and parts of Mexico. Some Native American tribes local to this region consider S. apiana to be sacred and burn the leaves as incense for purification ceremonies. The plant has been used to treat sore throats, coughs, chest colds, upper respiratory infections and poison oak rashes. The aqueous ethanolic extract of S. apiana showed moderate CB1 activity (58.3% displacement). Chromatographic purification of the ethanolic extract on silica gel column led to isolation of nine compounds: rosmadial (I), carnosol (II), 16-hydroxycarnosol (III), sageone (IV), cirsimaritin (V), salvigenin (VI), oleanolic acid (VII), 3β,28-dihydroxy-urs-12-ene (VIII), and ursolic acid (IX). The structures of the isolated compounds were determined by their 1D, 2D NMR and MS spectral data. All the fractions and isolated compounds were tested for cannabinoid and opioid receptor binding.

Nepetaefolins A-J, Cytotoxic Chinane and Abietane Diterpenoids from Caryopteris nepetaefolia

Nepetaefolins A-J (1-10) and seven known compounds were isolated from the whole plant of Caryopteris nepetaefolia. The absolute configurations of 1-3 were determined from single-crystal X-ray diffraction and spectroscopic data. Compounds 6 and 7, with IC₅₀ values of 6.3-9.0 μM, showed higher cytotoxicity than paclitaxel in one non-small-cell lung cancer, patient-derived xenograft (PDX) model when tested using PDX models and the adenosine triphosphate-tumor chemosensitivity assay (ATP-TCA).

Anti-inflammatory and analgesic activity of carnosol and carnosic acid in vivo and in vitro and in silico analysis of their target interactions

BACKGROUND AND PURPOSE

The diterpenoids carnosol (CS) and carnosic acid (CA) from Salvia spp. exert prominent anti-inflammatory activities but their molecular mechanisms remained unclear. Here we investigated the effectiveness of CS and CA in inflammatory pain and the cellular interference with their putative molecular targets.

EXPERIMENTAL APPROACH

The effects of CS and CA in different models of inflammatory pain were investigated. The inhibition of key enzymes in eicosanoid biosynthesis, namely microsomal prostaglandin E2 synthase-1 (mPGES-1) and 5-lipoxygenase (5-LO) was confirmed by CS and CA, and we determined the consequence on the eicosanoid network in activated human primary monocytes and neutrophils. Molecular interactions and binding modes of CS and CA to target enzymes were analyzed by docking studies.

KEY RESULTS

CS and CA displayed significant and dose-dependent anti-inflammatory and anti-nociceptive effects in carrageenan-induced mouse hyperalgesia 4 h post injection of the stimuli, and also inhibited the analgesic response in the late phase of the formalin test. Moreover, both compounds potently inhibited cell-free mPGES-1 and 5-LO activity and preferentially suppressed the formation of mPGES-1 and 5-LO-derived products in cellular studies. Our in silico analysis for mPGES-1 and 5-LO supports that CS and CA are dual 5-LO/mPGES-1 inhibitors.

CONCLUSION AND IMPLICATIONS

In summary, we propose that the combined inhibition of mPGES-1 and 5-LO by CS and CA essentially contributes to the bioactivity of these diterpenoids. Our findings pave the way for a rational use of Salvia spp., traditionally used as anti-inflammatory remedy, in the continuous expanding context of nutraceuticals.

LINKED ARTICLES

This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc.

ent-Abietane and Tigliane Diterpenoids from the Roots of Euphorbia fischeriana and Their Inhibitory Effects against Mycobacterium smegmatis

An investigation on the bioactive chemical constituents of the roots of Euphorbia fischeriana has been conducted, with 21 diterpenoids obtained using various chromatographic techniques. On the basis of spectroscopic data analysis, the new compounds were elucidated as four ent-abietane-type diterpenoids (1-4) and four tigliane-type diterpenoids (13-16). Also obtained were eight known ent-abietane (5-12) and five known tigliane (17-21) diterpenoids. The potential antituberculosis effects of these diterpenoids were evaluated using a Mycobacterium smegmatis model. The most potent compound according to the in vitro bioassay used was 17-hydroxyjolkinolide B (12) (MIC 1.5 μg/mL).

Three New Abietane-Type Diterpenoids from Callicarpa macrophylla Vahl

Three new abietane-type diterpenoids, named callicapoic acid M3 (1), callicapoic acid M4 (2) and callicapoic acid M5 (3), were isolated from the Callicarpa macrophylla Vahl. Their structures were established by spectroscopic techniques (IR, UV, MS, 1D and 2D NMR). All the isolated three compounds were evaluated for inhibitory activity on NO production in LPS-activated RAW 264.7 macrophage cells by using MTT assays. Compounds 1, 2 and 3 showed potent inhibitory activity, with inhibition rates of 34.47–40.13%.

Comparative Analysis of the Major Chemical Constituents in Salvia miltiorrhiza Roots, Stems, Leaves and Flowers during Different Growth Periods by UPLC-TQ-MS/MS and HPLC-ELSD Methods

Salvia miltiorrhiza is a traditional Chinese herbal medicine containing multiple components that contribute to its notable bioactivities. This article investigated the distribution and dynamic changes of chemical constituents in various parts of S. miltiorrhiza from different growth periods. An ultra-high performance liquid chromatography-triple quadrupole mass spectrometer (UPLC-TQ-MS/MS) and high-performance liquid chromatography coupled with evaporative light scattering detector (HPLC-ELSD) methods were developed for accurate determination of 24 compounds (including phenolic acids, flavonoids, triterpenes, and saccharides) in S. miltiorrhiza. The established methods were validated with good linearity, precision, repeatability, stability, and recovery. Results indicated that there were category and quantity discrepancies in different parts of the plant, for the roots mainly contained salvianolic acids and tanshinones, and most of the saccharides are stachyose. In the aerial parts, salvianolic acids, flavonoids, and triterpenes, except the tanshinones, were detected, and the saccharides were mainly monosaccharides. Dynamic accumulation analysis suggested the proper harvest time for S. miltiorrhiza Bunge was the seedling stage in spring, and for the aerial parts was July to August. This study provided valuable information for the development and utilization value of the aerial parts of S. miltiorrhiza and was useful for determining the optimal harvest time of the plant.

Abietic acid isolated from pine resin (Resina Pini) enhances angiogenesis in HUVECs and accelerates cutaneous wound healing in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Resin known as Resina Pini is listed in the Korean and Japanese pharmacopoeias and has been used for treating skin wounds and inflammation. Resin is composed of more than 50% abietic acid and 10% neutral substances.

OBJECTIVE

In the present study, the wound-healing effects of abietic acid and the possible underlying mechanism of action were investigated in various in vitro and in vivo models.

MATERIALS AND METHODS

The effects of abietic acid on tube formation and migration were measured in human umbilical vein vascular endothelial cells (HUVECs). Protein expression of mitogen-activated protein kinase (MAPK) activation was evaluated via Western blotting analysis. The wound-healing effects of abietic acid were assessed using a mouse model of cutaneous wounds.

RESULTS

The results showed that abietic acid enhanced cell migration and tube formation in HUVECs. Abietic acid induced significant angiogenic potential, which is associated with upregulation of extracellular signal-regulated kinase (ERK) and p38 expression. Additionally, 0.8μM abietic acid-treated groups showed accelerated wound closure compared to the controls in a mouse model of cutaneous wounds.

CONCLUSION

The current data indicate that abietic acid treatment elevated cell migration and tube formation in HUVECs by the activation of ERK and p38 MAPKs. We suggest that abietic acid can be developed as a wound-healing agent.

Isolation, structure elucidation, and induction of hepatoma cell apoptosis of abietane diterpenoids from Abies faxoniana

Two new abietane diterpenoids (1-2) and 13 known compounds (3-15) were characterized from the branches and leaves of Abies faxoniana. The chemical structures of the new diterpenoids (1-2) were determined through the analysis of various 1D/2D NMR techniques. Compound 3 is 151,617-trinor-abietane diterpenoid conjugated with a three-membered epoxide ring. The isolated diterpenoids were tested for their cytotoxicities. Among them, compound 3 exhibited the strongest antiproliferative effect against human hepatoma cell SMMC7721 with an IC₅₀ value of 12.5 μM. To elucidate the preliminary mechanism responsible for compound 3-induced inhibition of cell proliferation, we investigated the effects of compound 3 on apoptosis, cell cycle progression, and reactive oxygen species generation in SMMC7721 cells. The results showed that compound 3 induced cell apoptosis and excessive ROS production, but did not change the cell cycle distribution in SMMC7721 cells.

Ent-Abietanoids Isolated from Isodon serra

Four new ent-abietane diterpenoids, along with four known ones were isolated from the aerial parts of Isodon serra, a traditional Chinese folk medicine. The new diterpenoids were named as serrin K (1), xerophilusin XVII (2), and enanderianins Q and R (3 and 4), while the known ones were identified as rubescansin J (5), (3α,14β)-3,18-[(1-methylethane-1,1-diyl)dioxy]-ent-abieta-7,15(17)-diene-14,16-diol (6), xerophilusin XIV (7), and enanderianin P (8), respectively. Their structures were elucidated by extensive spectroscopic analysis and comparison with the literature. Compound 1 showed remarkable inhibitory activity towards NO production in LPS-stimulated RAW264.7 cells (IC₅₀ = 1.8 μM) and weak cytotoxicity towards five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, SW480).

[Optimize ethanol-extraction procedure of Shenlian granules by orthogonal design with pharmacodynamics index]

To optimize the ethanol extraction process for Shenlian formula. On the basis of the pharmacodynamics index for different extraction process routes, the contents of salvianolic acid B, tanshinone ⅡA and berberine, as well as the extraction ratio in different experimental schemes were used as the ethanol extraction examining indexes, and multi-criterion synthesizing grading method was used for data analysis to optimize and verify the ethanol-extraction process conditions in orthogonal experiment. The optimum ethanol extraction process was as follows: adding 60% ethanol, 10 times amount, extracting for 2.0 h each time for a total of 2 times. This extraction process showed good stability and availability.

ent-Strobane and ent-Pimarane Diterpenoids from Siegesbeckia pubescens

Two strobane diterpenoids, strobols A (1) and B (2), 15 new pimarane diterpenoids (3-6 and 8-18), and the known compounds kirenol (19), darutigenol (20), and ent-2β,15,16,19-tetrahydroxypimar-8(14)-ene (7) were isolated from the aerial parts of Siegesbeckia pubescens Makino. The structures of the new compounds were established based on the interpretation of HRESIMS and NMR analysis. The configurations of 1, 6, and 17 were confirmed by X-ray crystallographic data. Compounds 3, 5, and 11 inhibited the migration of MB-MDA-231 breast cancer cells induced by the chemokine epithelial growth factor, with IC₅₀ values of 4.26, 3.45, and 9.70 μM, respectively.

New Abietane and Kaurane Type Diterpenoids from the Stems of Tripterygium regelii

Eleven new abietane type (1‒11), and one new kaurane (12), diterpenes, together with eleven known compounds (13-23), were isolated and identified from the stems of Tripterygium regelii, which has been used as a traditional folk Chinese medicine for the treatment of rheumatoid arthritis in China. The structures of new compounds were characterized by means of the interpretation of high-resolution electrospray ionization mass spectrometry (HRESIMS), extensive nuclear magnetic resonance (NMR) spectroscopic data and comparisons of their experimental CD spectra with calculated electronic circular dichroism (ECD) spectra. Compound 1 is the first abietane type diterpene with an 18→1 lactone ring. Compound 19 was isolated from the plants of the Tripterygium genus for the first time, and compounds 14-17 were isolated from T. regelii for the first time. Triregelin I (9) showed significant cytotoxicity against A2780 and HepG2 with IC50 values of 5.88 and 11.74 µM, respectively. It was found that this compound was inactive against MCF-7 cells. The discovery of these twelve new diterpenes not only provided information on chemical substances of T. regelii, but also contributed to the chemical diversity of natural terpenoids.